Device for making coffee and espresso beverages in microwave oven

ABSTRACT

According to the present invention, water is placed in a water reservoir constructed of plastic microwave-transparent, pressure-resistant material. A funnel positioned on the upper surface of filter compartment is supported on the upper edges of the water reservoir with the spout extending downwardly into the water reservoir. A lower filter is placed into the filter compartment, and coffee grounds or other espresso particulate substance is placed on upper surface of the lower filter. An upper filter is then positioned on the upper surface of filter compartment to restrain the coffee grounds or other particular substance during brewing. A filtrate reservoir is placed over the funnel, and twisted, thereby engaging threads to join the water reservoir and the filtrate reservoir. A filtrate splash cover is attached to the upper edges of the filtrate reservoir. The assembled espresso device is placed into a microwave oven. As water in the water reservoir begins to boil, steam is generated, and boiling water is displaced upwards through the funnel and grounds, forming espresso. The filtrate splash cover provides for both venting and fluid retention during brewing. A resilient gasket, in conjunction with a plurality of vent passages, provides an additional path for pressure relief. The espresso is automatically emptied into the filtrate reservoir, which is designed to function as a drinking cup for individually-sized portions.

CROSS REFERENCE

This is a continuation application of Ser. No. 08/610,840 filed Mar. 5,1996, now U.S. Pat. No. 5,747,782, which is a continuation of Ser. No.08/458,309 filed Jun. 2, 1995, now abandoned, which is a continuation ofSer. No. 08/037,814 filed Mar. 26, 1993, now abandoned. The entirespecification and all the claims referred to are hereby incorporated byreference to provide continuity of disclosure.

TECHNICAL FIELD

The present invention relates to a device and process for making coffeeand espresso (sometimes called "expresso") beverages, and moreparticularly, but not exclusively, to a device and process for makingcoffee or espresso coffee in a microwave oven.

BACKGROUND OF THE INVENTION

In the beverage industry, the espresso process involves forcing hotwater or steam under pressure through a particulate substance. Thegeneral method of making espresso coffee is well known. It involves theprocess or method of forcing hot water or steam through conventionalcoffee grounds or some extra fine coffee grounds. This method for makingcoffee differs significantly from the common methods for makingdrip-type or percolation coffees. The espresso coffee may be brewed witha mixture of espresso coffee grounds and cinnamon or other flavoredsyrups such as almond, orange, hazelnut, chocolate and the like.Espresso coffee generally is a dark full-bodied brew and may also beserved as cappucino, caffe latte, caffe Americano, doppio, or macchiato.

Microwave ovens are widely used and known for a variety of heatingtasks, including the heating of water for instant beverages or heatingother beverages and foods. In addition, several devices have beenproposed for brewing coffee in microwave ovens.

U.S. Pat. No. 4,104,957 issued Aug. 8, 1978 (Freedman et. al.) disclosesa coffee brewing appliance comprising a carafe, a filter that fits inthe neck of the carafe, and a water reservoir located over the filter.The water reservoir communicates with the filter by way of athermally-controlled valve. When water in the water reservoir is heatedby microwave radiation, the valve opens, allowing the water to flow intothe filter, extracting coffee constituents from coffee grounds in thefilter, so that a coffee beverage accumulates in the carafe.

U.S. Pat. No. 4,577,080 issued Mar. 18, 1986 (Grossman) discloses anappliance similar to that of Freedman et. al., except that instead ofusing a thermally-controlled valve to prevent cold water from the waterreservoir from contacting coffee grounds in a filter, a body ofnon-toxic wax melts when the water reaches the desired temperature.

U.S. Pat. No. 4,721,835 issued Jan. 26, 1988 (Welker) discloses a devicefor brewing coffee in a microwave oven. The device comprises a jughaving a top configured as a filter. Water and coffee grounds are placedin the jug, and the filter is fitted in the mouth of the jug. When thecoffee has brewed, it can be poured from the jug, while the coffeegrounds are retained by the filter.

U.S. Pat. No. 4,386,109 issued May 31, 1983 (Bowen et. al.) discloses anespresso coffee maker for use in a microwave oven. The water is storedin a microwave transparent reservoir which is adjacent to an aluminumpot. The pot and reservoir are coupled in a fixed spatial relationshipby a collar. The collar includes a strainer which presses against alayer of coffee grounds when the collar is secured to the reservoir. Thecompressed coffee grounds in combination with the strainer for apressure resistant seal over the opening of the reservoir. The water inthe reservoir is heated by microwave energy. The pressure rises to alevel sufficient to force steam and water in a downward directionthrough the coffee grounds into the pot, which stores the espressocoffee.

U.S. Pat. No. 4,381,696 issued May 3, 1983 (Koral) discloses a coffeebrewing appliance that is generally similar to that disclosed byFreedman et. al.

U.S. Pat. No. 4,345,512 issued Aug. 24, 1982 (Moore) discloses a teainfuser for use in a microwave oven. The tea infuser, instead of beingmade of metal, is made of microwave-transparent plastic material.

U.S. Pat. No. 5,012,059 issued Apr. 30, 1991 (Boatman) discloses adevice for heating water in a microwave oven. In Boatman's device, wateris heated in a water reservoir, then forced from the water reservoirthrough a tube into a heating chamber, where it is further heated priorto draining through a filter filled with coffee grounds.

U.S. Pat. No. 4,990,734 issued Feb. 5, 1991 (Hirsch et. al.) discloses amethod of preparing coffee where a mixture of water and coffee groundsis heated with microwave radiation, whereby a pressure gradient isproduced across a filter, forcing filtrate into a vessel.

German No. OS 3,206,803 includes, seated one on the other, a coffee pot,a filter to receive coffee, and a water container. The water containeris pervious to microwave radiation and the filter is developed so thatsubstantially no liquid can pass through the filter under atmospheric orambient pressure. The device is placed in a microwave oven in which themicrowave radiation brings the water in the water container to a boil,while the coffee remains screened off. The formation of steam developssuch a high pressure in the water container (up to 3.45 bar) that thewater is forced through the filter.

SUMMARY OF THE INVENTION

One of the objects of the present invention is to provide a safe andconvenient method and device for brewing coffee or espresso coffee, aswell as other espresso beverages such as cappucino, caffe latte, caffeAmericano, doppio or macchiato, in a microwave oven.

Another object of the present invention is to provide a device formaking coffee or espresso beverages in a microwave oven, from whichdevice one may conveniently drink individually-sized servings.

Still another object of the present invention is to provide a device formaking coffee or espresso beverages in a microwave oven and providingfor adequate pressure-relief and/or splashing safeguards.

Yet another object of the invention is to provide a device for makingcoffee or espresso beverages, in particular espresso coffee, in amicrowave oven while preventing messy splashing or bubbling over of thebeverage.

According to the present invention, water is poured into a waterreservoir made of a plastic microwave-transparent, pressure-resistantmaterial suitable for use with beverages. After filling the waterreservoir with water, a removable funnel, consisting of a cylindricalfilter compartment and spout, is mounted on upper edges of the waterreservoir with the spout of the funnel extending downwardly into thewater reservoir. A lower filter is positioned into the filtercompartment and coffee grounds, or other espresso particulate substance,are placed on upper surface of the lower filter.

An upper filter is then positioned on the upper edges of the filtercompartment, thereby enclosing and restraining the espresso particulatesubstance. A filtrate reservoir is threadably engaged to the waterreservoir such that the filter compartment is enclosed entirely andgenerally intermediate the filtrate reservoir and water reservoir. Apressure dissipator is positioned within the filtrate reservoir. Afiltrate splash cover is mounted on the upper edge of the filtratereservoir.

The microwave espresso device is placed into a microwave oven, which isthen set for about two minutes, depending upon the power of themicrowave oven, and the quantity of espresso being brewed, and sea levelelevation. Microwave radiation from the microwave oven heats the waterin the pressurized water reservoir, causing steam to form and water toboil. As the water in the water reservoir begins to boil, steam pressuredevelops and begins to displace the boiling water, causing boilingliquid and steam to rise upwards through the spout of the funnel,through the filters and espresso substance in the filter compartment,and through the pressure dissipater into the filtrate reservoir. Thecoffee or espresso coffee thus is brewed.

In the event of overheating or an excessive buildup of pressure withinthe espresso device, a pressure relief valve is provided. A resilientgasket is positioned between the funnel flange and the ring bottom ofthe filtrate reservoir. A plurality of vent passages connect theinterior of water reservoir and the lower surface of the gasket. Thegasket, in conjunction with the vent passages, serves as a pressurerelease valve. Upon high pressures, the gasket deforms and permits arelease of high pressure steam from the water reservoir into theatmosphere.

The filtrate splash cover serves as a splash guard to prevent release ofbubbles or pressurized fluid into the microwave oven. The splash coveralso provides for venting. Upon removal of the filtrate splash cover,the espresso may be imbibed directly from the filtrate reservoir, whichis designed to function as a drinking cup. An insulation jacket or ahandle is affixed to the exterior surface of the espresso device forhandling and lifting the hot device.

The present invention thus provides a simple, safe, inexpensive, andconvenient means for brewing coffee and espresso beverages in themicrowave oven. Other objects, advantages, and novel features of thepresent invention will become apparent from the following descriptionand drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional representation of the microwave espressodevice.

FIG. 2 is a cross-sectional representation of the water reservoir.

FIG. 3 is a cross-sectional representation of the funnel.

FIG. 4 is a detail of the pressure relief valve.

FIG. 5 is a plan and cross-sectional view of the upper filter.

FIG. 6 is a plan view of the lower filter.

FIG. 7 is an elevation of the lower filter.

FIG. 8 is a cross-sectional representation of the filtrate reservoir.

FIG. 9 is a plan view of the pressure dissipater.

FIG. 10 is a cross-sectional representation of the filtrate splashcover.

FIG. 11 is a cross-sectional representation of the splash guard sectionof the filtrate splash cover.

FIG. 12 is a cross-sectional representation of the cover section of thefiltrate splash cover.

FIG. 13 is a plan view of the cover section.

FIG. 14 is a cross-sectional representation of an alternative funnelhaving a removable filter canister.

FIG. 15 is a cross-sectional representation of the filter canister offunnel shown in FIG. 14 and its top filter in the open position.

FIG. 16 is a cross-sectional representation of the top filter of thefilter canister of the funnel shown in FIG. 14.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, there is generally shown a microwave espressodevice 2 embodying the invention. FIG. 1 is a cut-away cross section ofthe exterior surface 3 of the espresso device. The espresso device isgenerally constructed of a plastic microwave-transparent,pressure-resistant material suitable for contact with beverages. Bymicrowave-transparent, it is meant that microwave energy will passthrough the material without substantial loss of energy.

Appropriate materials include Polyethylene Terephthalate (PET),polyether imide (ULTEM), or polyether imide-polycarbonate blend (ULTEMLTX SERIES).

The espresso device 2 includes a cylindrical water reservoir 4 having apressure relief valve 6; a filter apparatus 8 for holding coffee groundsor other espresso particulate substance; a cylindrical filtratereservoir 12, which detachably connects to the water reservoir 4; afunnel 10 for holding the filter apparatus 8 and for conducting steamand water from the water reservoir 4 to a filtrate reservoir 12; apressure dissipater 72 integrally molded with the filtrate reservoir 12;a gasket 14 inserted between a funnel flange 16 of the funnel 10 and thering bottom 68 of the filtrate reservoir 12 to form part of the pressurerelief valve 6; and a detachable filtrate splash cover 18.

The water reservoir 4 is threadably and releasably engaged to thefiltrate reservoir 12 at connection 11. This engagement clamps theremovable funnel 10 to the upper edge 32 of the water reservoir 4, andfurther holds the gasket 14 in position between ring bottom 68 of thefiltrate reservoir 12 and the funnel flange 16 and/or upper edge 32 ofthe water reservoir 4.

The funnel 10 includes a spout 44 and cylindrical filter compartment 42.The filter apparatus 8 includes a removable lower filter 20 and aremovable upper filter 22. The filtrate splash cover 18 includes a coversection 24 and a splash guard 26. The water reservoir 4 provides apressurized chamber for the containment of steam and liquid during theespresso making process. The filtrate splash cover 18 acts as a splashguard, breaks down bubbles, and provides for venting. The filtratereservoir 12, after removal of filtrate splash cover 18, provides ameans for direct consumption of the finished beverage. The espressodevice may be sized for an individual serving or for multiple, largerservings.

To operate, a suitable quantity of water is poured into the waterreservoir 4, and the circular funnel flange 16 is placed on the upperedge 32 of the water reservoir 4. The spout 44 extends downwardly intothe water reservoir 4. The circular lower filter 20 is positioned withinthe lower portion of the filter compartment 42 to form a seal or seatbetween the spout 44 and the filter compartment 42. Ground coffee, orother espresso particulate substance, either loose or contained in apaper bag or other filter, is placed on the upper surface of the lowerfilter 20. Paper filters could be approximately 20 microns. The circularupper filter 22 is attached to the upper edges of filter compartment 42.The filtrate reservoir 12 is threadably engaged or otherwise affixed atconnection 11 to the water reservoir 4 such that the filter compartment42 is enclosed entirely and located generally intermediate the filtratereservoir 12 and water reservoir 4. The filters 20 and 22 may be shapesother than circular. The cover section 24 is detachably engaged with theupper surface 2 of the filtrate reservoir 12, and the splash guard 26 issnapped into place over the cover section 24.

Upon application of the microwave energy and as water in the waterreservoir 4 heats and begins to boil, steam pressure in the waterreservoir 4 forces boiling liquid and steam to rise upwards through thespout 44, lower filter 20, espresso particulate substance, upper filter22, and the pressure. dissipater 72 into the filtrate reservoir 12. Thefiltrate splash cover 18 serves to break up bubbles and deflect liquidinto the filtrate reservoir 12 and to contain steam within the filtratereservoir, where it may cool and condense. The filtrate splash cover 18thereby limits the undesired escape of fluid and steam into themicrowave oven. This improves the efficiency of the process andminimizes the necessary size of the water reservoir 4 for devicesbrewing individual portions. The process continues until most of thewater has been discharged into the filtrate reservoir 12. Espresso maybe brewed in approximately two minutes, depending upon the power of theoven, the quantity of espresso being brewed, and the atmosphereconditions.

Referring to FIG. 2, the water reservoir 4 comprises a circular base 28and a cylindrical water reservoir wall 30 having an upper edge 32 and alower edge 34. The lower edge 34 of the water reservoir wall 30 connectsto the circular base 28. Just below the upper edge 32, there is anannular boss 36 on the outside of the water reservoir wall 30. Inanother alternative, the boss 36 may be a series of bossescircumferentially-spaced on the outside of the water reservoir wall 30.On the annular boss 36, there are threads (not shown) which are designedfor the swift engagement of reciprocal threads (not shown) onsys thefiltrate reservoir 12 (FIG. 8). Near the upper edge 32, the insidediameter of the water reservoir wall 30 abruptly increases, therebydefining an annular, reservoir ledge 38. The outside of the waterreservoir 4 is molded with ribs 40 for strength, ornamentation and toprovide a grip to comfortably tighten the final assembly.

Referring to FIG. 3, there is generally shown the funnel 10, whichcomprises a cylindrical filter compartment 42, a spout 44, and thefunnel flange 16. The funnel flange 16 connects, and defines atransitional passageway between, the filter compartment 42 and the spout44. The funnel flange 16 includes an interior ledge 47 for positioning,supporting, and seating the lower filter 20.

The filter compartment 42 has an inside diameter which is generallyconstant, except that near the top of the filter compartment 42, theinside diameter abruptly increases, thereby defining an annular, filtercompartment ledge 46, which is used to support, position, and seat theupper filter 22 during operation. The inside diameter of the funnelflange 16 is variable, thereby providing a smooth transition between thefilter compartment 42 and the inside of the spout 44.

Referring to FIG. 4 (a detail of FIG. 1), the outside diameter of thefunnel flange 16 is somewhat less than the inside diameter 49 of theupper portion of the water reservoir 4, thereby defining an annularspace 48 when the funnel flange 16 is set in its operating position onthe reservoir ledge 38.

The pressure relief valve 6 comprises the gasket 14, four flange grooves50, and a plurality of gaps 52 located in the threads on the annularboss 36 and in the reciprocal threads on the filtrate reservoir 12. Moreor less flange grooves may be appropriate. The flange grooves 50 providea passage between the water reservoir 4 and the annular space 48. Whenpressure in the water reservoir 4 exceeds a certain limit, preferably inthe range of 40 to 60 psi, steam escapes through the annular space 48,underneath the gasket 14 which resiliently deforms, and through theplurality of gaps 52 in the outside and inside threads. As shown in FIG.1, the released steam passes through a passage formed by the lower wall65 of the filtrate reservoir 12 and the outer surface of the waterreservoir 4 and escapes at escape opening 53.

The gasket 14 is made of a resilient material such as food grade siliconrubber. The gasket is designed to fit into an annular space between thering bottom 68 of the filtrate reservoir 12 and the top surface of thefunnel flange 16. The arrangement shown in FIG. 4, where the gasket hasa hardness of approximately 60 durameters, was found to provide pressurerelief at approximately 50-60 psi. Other gasket hardnesses or pressurerelief settings are appropriate depending on the circumstances anddesign considerations. It should be noted that the outside diameter ofthe gasket 14 is somewhat greater than the outside diameter of thereservoir ledge 38, thereby covering or overlapping the annular space48. When the filtrate reservoir 12 is threaded into the water reservoir4, the removable gasket 14 is held in position.

Alternative pressure relief valves include the upper filter 22 wherefault lines are created for the purpose of breaking under pressure andthus opening up a larger passage for pressure relief.

Referring to FIG. 5, the upper filter 22 has a plurality of perforations54 of a size and number sufficient to retain the espresso particulatesubstance, while allowing passage of steam and water. The size of theopenings typically can range from 0.020 to 0.032 inches in diameter;although other sizes may be suitable depending on the size of theparticulate substance; the number of openings can range from 100 to 150.The typical opening size is 0.032 inches, and the typical number is 124.The upper filter 22 has an outside diameter 55 which is slightly lessthan that of the filter compartment ledge 46 (shown in FIG. 3), for easeof placement of the upper filter 22 on, and removal of the upper filter22 from, the filter compartment ledge 46. A central orifice 56 definedby the upper filter 22 is sized to accommodate passage of a filterhandle 58, which is shown in FIGS. 6 and 7.

Referring to FIGS. 6 and 7, the lower filter 20 comprises the filterhandle 58, and a lower circular filter disc 60. The filter handle 58,which is generally cylindrical, is perpendicularly connected to thecenter of the lower filter disc 60. The lower filter disc 60 has aplurality of perforations 62 of a size and number sufficient to allowfree movement of steam and water, while retaining coffee grounds orother espresso particulate substance. The size of the openings can rangefrom 0.032 to 0.065 inches in diameter; the number of openings typicallycan range from 100 to 150. The typical opening size is 0.040 inches, andthe typical number is 124. The diameter 61 of the lower filter disc 60,is slightly less than the inside diameter of the filter compartment 42to facilitate displacement, and manual removal and replacement, of thelower filter 20.

Referring to FIG. 8, the filtrate reservoir 12 includes a generallycylindrical filtrate reservoir wall 64, a lip 66, a ring bottom 68, afilter compartment sleeve 70, a conical pressure dissipater nozzle 72,and a reservoir sleeve 74.

The filtrate reservoir wall 64 connects to the ring bottom 68, which inturn connects to the conical filter compartment sleeve 70. The filtercompartment sleeve 70 is connected to the pressure dissipater 72.Preferably, the entire assembly is integrally molded or manufactured.

The lip 66, which is located at the top edge of the filtrate reservoirwall 64, is fluted slightly outward, and is rounded, to facilitatepouring, or sipping, of a beverage.

The reservoir sleeve 74 is a cylindrical shell which seamlesslycontinues the outside surface of the filtrate reservoir wall 64 andlower wall 65. The outside surface of the reservoir sleeve 74 and theoutside surface of the filtrate reservoir wall 64 and lower wall 65 arecovered with continuous foam insulation 76, such as foam silicon rubberor molded vinyl foam, to enable manual gripping of an otherwisepotentially hot surface. In another alternative, a handle (not shown),which may be of any of the well-known types used with coffee mugs, maybe integrally molded or otherwise attached to filtrate reservoir toenable manual gripping.

The inside surface of the reservoir sleeve 74 has a diameter slightlylarger than the outside diameter of the water reservoir 4, therebyfacilitating the placement of the reservoir sleeve 74 over a portion ofthe water reservoir 4. The reciprocal threads (not shown) on thefiltrate reservoir 12 are located in a thread area 75 on the insidesurface of the reservoir sleeve 74.

The ring bottom 68 has an outside edge 69 which is connected to thefiltrate reservoir wall 64, and an inside edge 71 which is connected tothe filter compartment sleeve 70.

The inside diameter of the filter compartment sleeve 70 is slightlylarger than the outside diameter of the filter compartment 42 (shown inFIG. 3) to facilitate the containment or covering of the filtercompartment 42 when the filtrate reservoir is positioned for operation.

Referring to FIGS. 8 and 9, the pressure dissipater 72 comprises anozzle 78 having two ends of different size, with the wide end having aflange 80 for connecting the nozzle 78 and the filter compartment 70.The other end has a spool-shaped cap 82. The cap includes a plurality ofexit orifices 84 and an opening 85 for a central pressure dissipationchamber 86, and an upper blind flange 88, the outside rim of which actsas a baffle to deflect fluid exiting the pressure dissipater 72.

The pressure dissipater flange 80 integrally connects the nozzle 78 tothe top rim of the filter compartment sleeve 70 (shown in FIG. 8), andholds down the upper filter 22 (shown in FIG. 1) during operation.

Referring to FIGS. 10 through 13, the filtrate splash cover 18 includesthe cover section 24 and splash guard 26, which when combined areremovably mounted upon the lip 66 of the filtrate reservoir 12.

The cover section 24 has a plurality of vent holes 90, lift knob 92,deflector portion 93, and annular ring 95. The annual ring 95 includes anotch 97 for cooperating mechanically with lip 66 of the filtratereservoir 12. The splash guard 26 includes approximately eight fingers94 and splash baffle 96.

More or less fingers may be appropriate depending upon the design. Thelower edge 95 of the splash baffle 96 connects to the fingers 94. Eachof the fingers has projecting tips 98 designed to releasably grip thelip 66 (FIG. 8) of the filtrate reservoir 12. The fingers 94 defineslots 100, which allow the fingers 94 to move independently of oneanother. Alternative releasable gripping arrangements may be used. Anupper, inside edge 106 of the splash baffle 96 defines a downwardlyextending angular surface 99 for deflecting downward the liquid whichpasses through the vent holes 90 of the cover section and a centralorifice 102, which vents the espresso device 2. An annular ledge 104 onthe inside of the splash guard 26 is designed to hold the cover section24 (shown in FIGS. 1 and 10) in place during microwave heating. Thefiltrate splash cover 18 serves to deflect pressurized liquid into thefiltrate reservoir 12, to limit the escape of steam, to furtherdepressurize the liquid, and to break up bubbles formed during thebrewing process, all designed to prevent or minimize the spraying orspillage of liquid into the microwave during the heating process.

Referring to FIGS. 14 through 16, an alternative funnel 108 is shown.The funnel 108 includes a cylindrical, self-contained coffee filtercanister 112, a funnel flange 122 and spout 124. The funnel flange 122includes an outer flange ring 110 and a cylindrical upstanding flangeprojection 111. The cylindrical upstanding flange projection 111 forms apocket for removably fitting the filter canister 112. The funnel flange122 connects and defines a transitional passageway between the filtercanister 112 and the spout 124.

The cylindrical filter canister 112 has an outer wall 115 and an innerwall 117 having a generally constant diameter in the lower portion. Atransitional section 119 increases the wall diameters of the upperportion of the filter canister 112. An. annular ledge 130 is formed atthe top of cylindrical wall of the filter canister 112. Although thefilter canister 112 and cooperative upstanding flange projection 111 arecylindrical, other shapes may be used.

An upper filter 116 is attached to the filter canister 112 at pin 123 ofconnection 118 and is seated on ledge 130 during operation. Pin 123 isattached to the ledge 130 of the filter canister 112. Referring to FIGS.15 and 16, the upper filter 116 is capable of sliding along the ledge130 and swiveling about pin 123 at connection 118 for access into theinside of canister 112. The upper filter 116 has a plurality ofperforations or openings (not shown) of size and number sufficient toretain the espresso particulate substance, while allowing passage ofsteam and water, similar to that shown in FIG. 5. The upper filter hasan annular crown 126 with inner crown edge 125, outer crown edge 127,and a pin opening 129. The upper filter 116 has an outside diameterwhich is substantially the same as the outside diameter of the upperportion of the filter canister 112, except there is a beveled portion120 formed out of the outer crown edge 127 and detent 129 whichcooperate with pin 121 mounted on the upper surface of the filtercanister 112. This connection permits the snapping into place foroperation, and subsequent swiveling of the upper filter 116. In anotheralternative (now shown); the upper filter may be hinged to the filtercanister or removable completely from the filter canister.

A lower filter 114 is integrally formed in the filter canister 112. Thelower filter 114 has a plurality of perforations or openings (not shown)of size and number sufficient to allow free movement of steam and water,while retaining coffee grounds or other espresso particulate substance,similar to that shown in FIG. 6.

Referring to FIG. 14, the filter canister 112 forms a seal with funnelflange 122 at annular groove 132 which is formed by annular abutment 134and the inside surface of upstanding flange projection 111 whichprojects from the upper surface of the outer ring flange 110. An annularfooting 136, having an angular or tapered inner surface, projects fromthe bottom edge of the filter canister 112 and seats upon the bottom ofgroove 132 or the abutment 134 to form a substantial seal to preventliquid and steam from bypassing the lower filter 114.

During the espresso process, the filter canister 112 offers additionalflexibility in that it can be removed from the funnel 108 to simplifythe placement of loose espresso particulate substance, loose coffeegrounds or filter bags or packets into the canister. The upper filter116 swivels to an open position for the placement of particulate andthen snaps back into place. The lower filter 114 is conveniently moldedintegrally into the canister. After the filter canister 112 is placedback into the pocket of the upstanding flange projection 111, theespresso process will proceed as previously described.

It will be appreciated that the present invention is not restricted tothe particular embodiment that has been described and illustrated, andthat variations may be made therein without departing from the scope ofthe invention as defined in the appended claims and equivalents thereof.

What is claimed is:
 1. A device for making beverages, comprising:A. afluid reservoir having an exterior and a fluid-receiving interior,wherein said interior is enclosed by a wall having inner and outersurfaces, said fluid reservoir having at least first and secondseparable wall portions, said first wall portion having a first sealingsurface and said second wall portion having a second sealing surface; B.a resilient seal having a first seal portion mating with said firstsealing surface and a second seal portion mating with said secondsealing surface for normally forming seals between the respective sealportions and sealing surfaces to seal said fluid-receiving interior,said first seal portion having an exterior portion exposed to pressureoutside of said fluid reservoir and an interior portion spaced from saidexterior portion; C. at least one vapor passage communicating betweensaid fluid-receiving interior and said first seal portion between saidinterior portion and said exterior portion, said at least one vaporpassage transmitting fluid pressure from said fluid-receiving interiorto said first seal portion, said vapor passage and seal defining apressure relief valve such that when pressure in the fluid-receivinginterior of the fluid reservoir exceeds a predetermined level, the sealwill deform to complete a passageway from the interior via at least onesaid vapor passage to the exterior of the fluid reservoir; and D. acompartment for retaining a beverage ingredient in contact with fluidfrom said fluid reservoir.
 2. The device of claim 1, wherein saidcompartment is a filter apparatus for holding a particulate substanceand having at least one filter for substantially retaining theparticulate substance while permitting the passage of liquid and steam.3. The device of claim 2, further comprising a funnel having a filtercompartment for mounting the filter apparatus, a spout extendingdownwardly into the fluid reservoir, and a funnel flange which connectsthe filter compartment to the spout.
 4. The device of claim 3, furthercomprising a filtrate reservoir detachably connectable to the fluidreservoir, the funnel connected to the fluid reservoir such that thefilter apparatus is generally intermediate the fluid reservoir andfiltrate reservoir.
 5. The device of claim 4, further comprising afiltrate splash cover detachably connected to the filtrate reservoir fordeflecting liquid into the filtrate reservoir, whereby, upon heatingwith microwave energy, the liquid and steam located in the fluidreservoir is pressurized and directed through the spout and the filterapparatus containing the espresso particulate substance, and into thefiltrate reservoir.
 6. The device of claim 4 wherein the filtratereservoir forms a drinking cup for consuming individually sizedservings.
 7. The device of claim 4 wherein insulation material isattached to the outside surfaces of the filtrate reservoir for holdingthe heated device.
 8. The device of claim 5 wherein the splash coverincludes a cover section and a splash guard removably mounted on thefiltrate reservoir, the cover section having a plurality of vent holesand a deflector portion to deflect pressurized liquid into the filtratereservoir, the splash guard including a vent and a splash baffle whichfurther defines a surface for deflecting liquid which escapes throughthe vent holes of the cover section downwardly back into the filtratereservoir.
 9. The device of claim 8 wherein the splash guard has a loweredge which has spaced fingers, the fingers having projecting tipsdesigned to removably grip the filtrate reservoir for mounting thereon.10. The device of claim 4 wherein the device includes a pressuredissipater integrally molded within the filtrate reservoir fordissipating the pressure of the liquid passing from the filter apparatusinto the filtrate reservoir.
 11. The device of claim 2 wherein filterapparatus includes an upper filter and a lower filter with theparticulate substance positioned intermediate the filters, the filtershaving a plurality of openings that permit the passage of liquid andsteam.
 12. The device of claim 11 wherein the openings rangeapproximately from 0.20 to 0.65 inches in diameter.
 13. The device ofclaim 4 wherein the fluid reservoir is threadably and releasably engagedto the filtrate reservoir.
 14. The device of claim 2, wherein saidfilter apparatus includes a spout extending downwardly into the fluidreservoir; whereby, upon heating with microwave energy, the liquid formssteam and the liquid and steam located in the fluid reservoir arepressurized and directed through the spout and the filter apparatus. 15.The device of claim 4 wherein the filtrate reservoir and fluid reservoircooperate to form a drinking cup for consuming individually-sizedservings.
 16. The device of claim 15 wherein insulation material isattached to the outside surfaces of the filtrate and fluid reservoirsfor holding the heated device.
 17. The device of claim 2 wherein thefilter apparatus is a removable self-contained filter canister havingside walls with top and bottom portions and a first filter and secondfilter attached to the top and bottom portions of the side walls,whereby the filter canister is capable of being removed from the filtercompartment for ease of filling with a beverage ingredient.
 18. Thedevice of claim 17 wherein the first filter is hingedly attached to oneof the portions of the filter canister.
 19. The device of claim 17wherein the first filter is attached through a pin to one of theportions of the filter canister, the first filter slidably swivels withrespect to the filter canister to open the canister for filling orremoving a particulate substance from the filter canister.
 20. Thedevice of claim 2 wherein the filter apparatus is a removableself-contained filter canister.